What is SPN 3058 FMI 9 & How to Solve It?

What is SPN 3058 FMI 9:

SPN 3058 FMI 9 refers to an issue with the Turbocharger Speed Sensor Circuit. FMI 9 typically indicates that the sensor is sending an out-of-range signal, leading to improper turbocharger operation and reduced engine performance.

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Why This Happens:

• Faulty turbocharger speed sensor.
  
• Damaged or shorted wiring in the sensor circuit.
  
• Loose or corroded sensor connectors.
  
• Malfunctioning turbocharger causing incorrect speed readings.
  
• ECM misinterpreting the sensor signal.
  
  

How to Fix It:

1. Inspect the turbocharger speed sensor for damage or malfunction.
   
2. Test the sensor’s signal to ensure it matches manufacturer specifications.
   
3. Check wiring and connectors for damage, corrosion, or loose connections.
   
4. Replace the faulty turbocharger speed sensor if necessary.
   
5. Inspect the turbocharger for performance issues.
   
   

How to Avoid It Before It Happens:

• Regularly inspect the turbocharger speed sensor and its wiring.
  
• Perform routine turbocharger maintenance to ensure optimal performance.
  
• Keep connectors clean and free from corrosion.
  
• Use diagnostic tools to monitor turbocharger system performance.
  
• Clue’s Equipment Maintenance services can monitor turbo system health to prevent sensor and performance issues.